In the production of ethylene oxide by the conventional oxygen process, it is known to obtain a gas at about 107.degree. C. and 19.6 atm. having the following typical composition:
______________________________________ C.sub.2 H.sub.4 38.26 vol. % O.sub.2 3.59 vol. % ETO 1.47 vol. % CO.sub.2 41.44 vol. % C.sub.2 H.sub.6 0.61 vol. % N.sub.2 4.70 vol. % Ar 8.56 vol. % H.sub.2 O 1.37 vol. % 100.00 vol. % ______________________________________
In the known absorption processes, this gas containing 1.47 vol. % of ethylene oxide is fed to a water-fed adiabatic absorber, from the top of which there exits an ethylene oxide-free gas containing 39.36 vol. % of C.sub.2 H.sub.4 and 42.46 vol. % of CO.sub.2, part of which is bled from the system to prevent the accumulation of inerts in the ethylene oxide reactor, and part of which is decarbonated before being recycled to the oxide reactor together with the remainder of the gas.
From the bottom of the absorber, a solution at a temperature of 62.degree. C. is obtained containing 1.92 weight % of ethylene oxide together with a certain quantity of C.sub.2 H.sub.4 and CO.sub.2. This solution is expanded to 5 atm. and is then preheated to 99.degree. C. and fed to a stripper operating at about atmospheric pressure, in which the ethylene oxide, ethylene and carbon dioxide are removed from the water by using a current of external steam.
The gas leaving the stripper at 98.degree. C. is cooled to 30.degree. C. and fed into a second water-fed adiabatic absorber in which the ethylene oxide is reabsorbed to produce a solution containing about 10 weight % of ethylene oxide, which is fed to the glycol production plant.
In order to clarify the differences between the known process and the process according to the present invention, a description is given hereinafter of the two processes.